Powellite (CaMoO₄) is the calcium molybdate — the molybdate analog of scheelite (CaWO₄, calcium tungstate) — and forms a continuous solid-solution series with scheelite. Named after explorer John Wesley Powell. Powellite is famous for its strong yellow-orange fluorescence under shortwave UV. Pune basalts (India) and the Mammoth Mine (Arizona) yield iconic specimens.
Key Facts
- Mohs hardness 3.5–4.
- Tetragonal; isostructural with scheelite (W endmember).
- Strong yellow-orange UV fluorescence (creamy yellow).
- Forms continuous solid-solution series with scheelite.
- Common in oxidized molybdenite-bearing deposits.
Notable Localities
Pune basalts (Maharashtra, India) yield iconic crystals on stilbite/heulandite matrix. Mammoth Mine (Arizona, USA) supplies American collector pieces.
Found at these Localities
- Maharashtra Deccan Traprock Zeolites (马哈拉施特拉德干玄武岩沸石产地)
